The Old Gods and their unique magic have been around us for some time already but we don't know the full extent of their power. There is no doubt that a weirdwood can grant you access to the past and the present, the real question is:
Will Bran Stark be able to see the future?
My initial answer was a rotund no when anyone would ask me about it but rereading and connecting all the elements has made me change my mind about it as I found evidence of it to my dismay. In his very third chapter, Bran Stark was shown the future by the three eyed raven.
Let me walk you through this fragment and its timeline.
He saw Winterfel as the eagles see it, the tall towers looking squat and stubby from above, the castle walls just lines in the dirt. He saw Maester Luwin on his balcony, studying the sky through a polished bronze tube and frowning as he made notes in a book.
There are no references of Maester Luwin's activities so it remains unclear if this is something happenning in the past or the present. My bet is on the past because the events go from the past (starting with the next one) to the present and finally the future.
He saw his brother Robb, taller and stronger than he remembered him, practicing swordplay in the yard with real steel in his hand.
Clearly the past, by the time Bran wakes up Robb has already taken a lot of responsability and after the kid was attacked Catelyn notices he has a sword made of steel.
He saw Hodor, the simple giant from the stables, carrying an anvil to Mikken’s forge, hefting it onto his shoulder as easily as another man might heft a bale of hay.
This could be any time just like Maester Luwin, unfortunately we can't track the secondary characters.
At the heart of the godswood, the great white weirwood brooded over its reflection in the black pool, its leaves rustling in a chill wind. When it felt Bran watching, it lifted its eyes from the still waters and stared back at him knowingly.
The weirdwood senses Bran and the timeline of the visions changes.
He looked east, and saw a galey racing across the waters of the Bite. He saw his mother sitting alone in a cabin, looking at a bloodstained knife on a table in front of her, as the rowers puled at their oars and Ser Rodrik leaned across a rail, shaking and heaving.
Present time, Catelyn and Ser Roger have already left to meet Ned by the time Bran wakes up.
A storm was gathering ahead of them, a vast dark roaring lashed by lightning, but somehow they could not see it.
Still in present time, Bran can predict the future. He can see the bigger picture even if they cannot.
He looked south, and saw the great blue-green rush of the Trident. He saw his father pleading with the king, his face etched with grief. He saw Sansa crying herself to sleep at night, and he saw Arya watching in silence and holding her secrets hard in her heart.
Present time too, Lady is about to be killed and Sansa is sad. Arya has already seen what is left of Micah and it has hurted her deeply.
The change is sudden and it is easy to dismiss it unless you read very carefully.
There were shadows all around them. One shadow was dark as ash, with the terrible face of a hound. Another was armored like the sun, golden and beautiful. Over them both loomed a giant in armor made of stone, but when he opened his visor, there was nothing inside but darkness and thick black blood.
Bran sees what Ser Gregor Clegane would become in AFFC, three books later. THREE BOOKS LATER. This is his first glimpse to the future.
He lifted his eyes and saw clear across the narrow sea, to the Free Cities and the green Dothraki sea and beyond, to Vaes Dothrak under its mountain, to the fabled lands of the Jade Sea, to Asshai by the Shadow, where dragons stirred beneath the sunrise.
We have a through Essos. Bran sees dragons waking up, stirring. Asshai by the Shadow might have dragons but the stirring part makes me think of Daenerys Targaryen becoming the Mother of Dragons in the very last chapter of AGOT.
This is a weakest point though, luckily there are more.
Finally he looked north. He saw the Wal shining like blue crystal, and his bastard brother Jon sleeping alone in a cold bed, his skin growing pale and hard as the memory of all warmth fled from him.
Bran sees Jon dead after he was killed in ADWD, four books later. FOUR BOOKS LATER.
And he looked past the Wall, past endless forests cloaked in snow, past the frozen shore and the great blue-white rivers of ice and the dead plains where nothing grew or lived. North and north and north he looked, to the curtain of light at the end of the world, and then beyond that curtain. He looked deep into the heart of winter, and then he cried out, afraid, and the heat of his tears burned on his cheeks.
Now you know, the crow whispered as it sat on his shoulder. Now you know why you must live.
“Why?” Bran said, not understanding, falling, falling.
Because winter is coming.
Winter is coming and with it the Long Night. The weirdwoods and Bloodraven show all this to Bran and more.
The magic of the Old Gods has access to the future in some cappacity so there is proof, to my dismay, that seeing the future is possible.